Part of the Nordic power system
Finland is part of the Nordic synchronous area. A synchronous area is an area in which the electricity grids are connected by alternating current connections. Finland is in the same synchronous area as Sweden, Norway and eastern Denmark.
Finland’s main grid is connected to Sweden’s grid by two 400 kV AC connections in northern Finland. In addition, there is a 220 kV AC connection from Inari to Norway.
In addition to AC connections, HVDC transmission links have been built: Fenno-Skan 1 from Rauma (transmission capacity: 400 MW) to Dannebo in Sweden and Fenno-Skan 2 (transmission capacity: 800 MW) from Rauma to Finnböle in Sweden. An HVDC transmission link connects Naantali to Åland (transmission capacity: 100 MW) and is owned and operated by Kraftnät Åland.
The Nordic synchronous area connects to other systems via direct current connections. For example, there are two direct current connections between Finland and Estonia: EstLink 1 (transmission capacity: 350 MW) and EstLink 2 (transmission capacity: 650 MW).
The current state of the power system in Finland is shown here. Svenska kraftnät, the transmission system operator in Sweden, provides information on the state of the power system in Scandinavia and the Baltic region in English and Swedish.
How DC and AC connections differ: At the moment, only AC connections are used within Finland. This is because AC connections generally represent better techno-economic value than DC connections when building above ground within the same synchronous area.
DC connections enable electricity transmission between two different synchronous areas, such as the Estlink 1 and Estlink 2 connections between Finland and Estonia. DC connections are also used within synchronous areas if they are techno-economically viable.
The System Operation Agreement (SOA) between the Nordic transmission system operators sets out the common principles for the operation of the Nordic power system. The SOA and its appendices are on the ENTSO-E website and in the list of appendices on this page. The SOA and its appendices are in English.
Attachments
- Nordic SOA Main Agreement
- Annex Emergency & Restoration
- Annex Load-Frequency Control & Reserves
- Regularly changing parameters
- Assessment of arrangements for exchange and sharing of FRR capacity between Finland and Estonia
- Assessment of arrangements for sharing of mFRR capacity between bidding zones DK1 and DK2
- Annex Electricity Balancing
- Annex Operational Planning
- Operational Procedure for Nordic Outage Planning Coordination
- Operational Procedure for Nordic Adequacy Assessment
- Annex Operational Security
- Joint operation between the Nordic subsystems
- Annex Capacity Allocation & Capacity Management
- Annex Forward Capacity Allocation